Profile Views counter and can also show who visited profiles. (Depends on the settings too)

Alternative private message system (users can't send private messages!), instead of sending private messages when a new comment arrives or when there's a new pending friend request, etc..Admins can switch to a different messaging system - see screenshots.

You can disable the complete plugin without deactivating it (just do it from the settings). You can disable profile comments as well as profile views counter among other things.

Screenshots - From 1.1
Member Profile - our own profile

View All Friends page

Friend Requests - User CP

View profile views list - this can be disabled in settings

View all comments

Viewing someone else's profile

Download
The plugin is attached to this post

Note:when you activate the plugin, all buddy lists will be cleared to make sure the plugin will work fine. I could make it to add requests according to the buddy lists but that would be a rather slow process for large boards.